Facebook rainbow profiles used by 26 million

Rainbows spread quickly all over Facebook this weekend to celebrate the Supreme Court decision that legalized same-sex marriage.

Over the past three days, 26 million people have super imposed rainbows over their Facebook(FB) profile pictures using a free tool provided by the company. The rainbow filter launched Friday and continued to gain steam over Pride weekend, garnering more than half a billion likes and comments all over the world.

Famous people including Russell Simmons, California Attorney General Kamala Harris, Leonardo DiCaprio, and Arnold Schwarzenegger, and Brazil's president Dilma Rousseff changed their profiles.

The tool was created by two Facebook interns during an internal hackathon last week.

Changing a profile picture is easily dismissed as low-effort activism. But for many people who are not typically political it was a way to quietly show support.

Facebook has long been a vocal supporter of LGBTQ rights. But many activists are still upset about the company's real-names policy that requires people use an "authentic" name that they can prove they're known by in the real world. Drag queens, sex workers, abuse survivors and Native Americans all say the policy discriminates against them.

In the US alone, more than 6 million people have identified as gay, lesbian, bi-sexual, transgender or gender non-conforming on the social network.